Production of gasolines having high knock rates from nitrogenous middle oils



l 2,839,45() AsoLINEs HAVING HIGH KNOGK RATES FROM NITROGENOUS MIOOL E OILS June 17, 1958 w.oE'r1-|NGER PRODUCTION OF G Filed March 21, 1955 NZSFOO 10:..

I IIII INVENTOR.' WILL-l OETTINGER BY MTM,

PRODUCTION F GASOLINES HAVING HIGH KNOCK RATES FROM NITROGENOUS-MIDDLE OILS Willi Oettinger, Ludwigshafen (Rhine), Germany, assignor to Badische Anilin- & Soda-Fabrik Aktiengesellschaft, Ludwigshafen (Rhine), Germany This invention relates to a new and `improvedprocess for the production of gasolines having high knock rates from nitrogenous middle oils.

It is already known to produce gasolines from nitrog' enous middle oils originating from tars `and cracking and destructive hydrogenation products, by destructive hydro genation in the presence of compounds of the metals of the th to 8th groups which have been applied to silicates..

It has now been found that the octane number of gasolines can be considerably raised, for example by 7 to 12 octane numbers, by subjecting the initial material, before the destructive hydrogenation, to an incomplete relining by catalytic pressure hydrogenation at temperatures of 350 to 460 C. and pressures of 10 to 300 atmospheres so that the incompletely purified `product still has a base number between 20 and 500, preferably between 27 and 400. The determina-donor this number is described in the periodical Angewandte Chemie, 1948, edition A, pages 330 to 333, An exact` potentie* metric rapid determination of the basic nitrogen content of oils," by Dr. Gg. Wittmann, and gives the nitrogen content in milligrams of NH3 per litre of initial material, i. e. a base number of 20 indicates that l litre-of the middle oil in question contains as much nitrogen as correspond to 20 milligrams of NH3.

Suitable initial materials include middle oils from tars, as for example from low temperature carbonization tars and coke oven tars as well as from low temperature carbonization tars of shales, also from the reaction products` obtained by hydrogenationof coals, ters and nitrogenous oils and their cracking products in the liquid phase. Such initial materials have a base number of about` 900` to 4000 or more. The middle oils may boil between 200 and 400 C., in particular 200 to 350 C.

It is already known to free these initial materials from sulfur, oxygen and nitrogenby catalyticrelining with hydrogen under pressure the relined product then having a base number within the limits of about l to a maximum of l0. This catalytic refining with hydrogen is carried out in known manner at 370 to 470` C., in particular at 390 to 460 C., and under a pressure of to 300 atmospheres, advantageously at 50 to 250 atmospheres, and a throughput of 0.5 to 2,Y volumes of initial material per volume of catalyst space per hour. Suitable catalysts are the known hydrogenation catalysts, such as the compounds, in particular the oxides and suldes, of the metals of the 5th to 8th groups ofthe periodic system, as for example molybdenum, tungsten, nickel, cobalt or the metals of the platinum group or palladium group as well as the comopunds of the heavy metals of the lst group. The mixtures of suliides or oxides of the metals of the 6th group with those of the 8th group are especially suitable, as for examplemolybdenum and/or tungsten with nickel aud/or cobalt, the

latter preferably being used in smaller amounts than the compounds of the metals of the 6th group. Thus for example the atomic ratio of the metals of the 8th group- States Patent O l 2,839,450 Patented June 1 7, 1958 to the metals of the 6th group may lie between 0.5 :10 and 9:10. The molybdates Aand tungstates of nickel and cobalt are also of advantage. These catalysts can be applied to carriers, such as active alumina, natural or synthetic silicates. Those synthetic silicates and aluminates are especially suitable in which the hydrogenating constituent, as for example nickel, cobalt, molybdenum or tungsten, forms a compound with the silicic acid or alumina, as for example nickel silicate or cobalt silicate, which can be produced by mutual precipitation.

In order to obtain products which are only partly rened and have a base number of 20 to 500, the conditions of temperature or/and throughput-independently of the pressures which are necessary for a complete reiining-are varied for example by lowering the reaction temperature by 10 to 30 C. or/ and increasing the throughput by 40% to 150%, in particular 50 to 100%.

Thus for` example middle oils from tars with a base number of 3000 to 4000 are completely rened at a certain temperature in the temperature range of 400 to 460 C. witha throughput of about 0.5-1 volume per volume per hour under an increased pressure of, for example, to 300 atmospheres, so that the reaction product has a base numberof 3 to 8. In order to obtain a reaction product with a base number of 200 to 400, the throughput must be l-2.5 volumes per volume per hour if the same temperature from within a temperature range of 400 to 460 C. is used as with a throughput of 0.5 to l volume per volume per hour in the case of complete refining. If the product having a base number of 200m 400 were to be obtained with `the throughput being from 0L5 to 1 volume per volume per hour the temperature should be by about 25 C. lower with the temperature range of 380 to 450 C. than the temperature used in the` aforesaid cases. The middle oils which are obtained by destructive hydrogenation of coals, tars and mineral oils with more than 0.1% of nitrogen in the sump phase usually have a base number of 1000 to 2000 and can be converted by catalytic rening by hydrogen under pressure at 400 to 460 C. and a throughput of about 1.0 to 1.5 volumes per volume per hour under a pressure of 100 to 300 atmosphere-3 into a product with a base number of 3 to 7. lf on the contrary at the same temperature the throughput is increased to 2 to 3 v./v./hr., the base number of the reaction product lies between 30 and 130. If the throughput is kept at 1.0 to 1.5 v./V./hr., the temperature must be lowered by 20 to 25 C. within the temperature range of 380 to 450 C. in order to obtain a base number within the desired range.

From this it may be seen that as compared with the temperature for complete refining within the range of 400 to 460 C., products with the desired base number are obtained by lowering the same by about 10 to 30 C. lf the temperature which is necessary for carrying out a` complete reiining is maintained, then the throughput chosen for the production of an incomplete rening is preferably about 70 to 150% higher and in general lies between 0.8 and 3 v.`/v./hr. If the temperature is only lowered moderately, for example by 5 to 15 C., it is also necessary to simultaneously carry out a moderate increase in the throughput, as for example by 40 to 75%.

`The exact conditions can readily be ascertained by preliminary tests. lf the stated upper limit of 500 for the base number is exceeded, the activity of the catalyst in the destructive hydrogenation subsides rapidly. It is surprising that by working within the stated limits of the base number there is practically no loss in activity or the cracking catalystV and a considerable improvement in the octane number of thegasoline is obtained.

The `subsequent destructive hydrogenation is carried out Ii in known manner at 330 C. to 550 C. and under a pressure of 150 to 700 atmospheres or more in the presence of compounds, in particular oxides or sulfides, of the heavy metals of the th to 8th groups of the periodic system, as for example vanadium, chromium, molybdenum or tungsten. The metal compounds are applied to natural, preferably to synthetically prepared, silicates. The silicates are preferably pretreated with acid or halogen or hydrogen halide, as for example hydrofiuoric acid or hydrogen fluoride. Suitable silicates are described -in the following examples.

The accompanying drawing is a brief schematic representation of the process of the invention illustrating the treatment of a nitrogeneous middle oil by catalytic refining followed by destructive hydrogenation to produce a high octane gasoline. The limiting operating conditions of temperature and pressure are identified in the drawing, and it will be understood that the throughput of the nitrogeneous middle oil for catalytic refining must be correlated with these limiting conditions, particularly the temperature as described hereinabove, such that the incompletely refined oil will have a base number of between 20 and 500.

The following examples will further illustrate this invention but the invention is not restricted to these examples.

Example I By catalytic destructive hydrogenation in the sump phase there is obtained from a crude oil cracking residue a middle oil with a specific gravity of 0.897, an initial boiling point of 220 C. and 92% of constituents boiling up to 350 C. The base number of this middle oil amounts to 1875 miligrams of NH3 per litre of oil.

This middle oil is led together With 2.3 cubic metres of fresh and circulated hydrogen per kilogram of oil under a pressure of 260 atmospheres over a catalyst consisting of 25% of tungsten sulfide and 3% of nickel sulfide on alumina at 390 C. with a catalyst loading of 1.7 kilograms of oil per litre of catalyst per hour. A product is obtained with a base number of 115 milligrams of NH3 per litre of oil. Similar results are also obtained when cobalt molybdate or cobalt sulfide or nickel sulfide catalysts on alumina basis are used instead of the aforesaid tungsten sulfide/ nickel sulfide catalysts.

The refined oil is led together with 1.5 cubic metres of hydrogen per kilogram of oil under a pressure of 260 atmospheres at 420 C. over a catalyst consisting of synthetic aluminum silicate with 3.5% of M003 (prepared according to application Serial No. 282,674). A gasoline containing 30% of aromatic compounds is obtained with an octane number of 82 according to the research method.

By working in the refining stage under otherwise identical conditions but with a catalyst loading of 0.8 kilogram per litre of catalyst per hour, a product is obtained with a base member of 5 milligrams of NH3 per litre of oil. In the subsequent destructive hydrogenation there is obtained over the same aluminum silicate catalyst a gasoline containing 18% of aromatic compounds and having an octane number of only 75 according to the research method.

Example 2 A middle oil having a boiling range of 205 to 350 C. and a base number of more than 3000 obtained by low temperature carbonization of Spanish shale is led under a pressure of 240 atmospheres together with fresh and circulated hydrogen at 390 C. over a catalyst consisting of nickel silicate with of M003. The catalyst loading amounts to 1 kilogram of oil per litre of catalyst per hour. The rened product has a base number of 370 milligrams of NH3 per litre of oil.

This refined product is led together with 2 cubic metres of hydrogen at 430 C. with a catalyst loading of 1.3 kilograms of oil per litre of catalyst per hour under a pressure of 240 atmospheres over synthetic aluminum silicate (prepared according to U. S. patent specification No. 2,335,388) with 3.5% of M003. A gasoline with an octane number of 74 according to the research method is obtained.

lf the above middle oil is refined so that the refined product has a base number of 6 milligrams of NH3 per litre, there is obtained by cracking over the above-mentioned catalyst a gasoline with an octane number of only 65 according to the research method.

Example 3 A sump phase middle oil with a base number of 1050 milligrams of NH3 per litre of oil arising from the sump phase destructive hydrogenation of Near East crude oil distillation residue is led together with 2 cubic metres of hydrogen under a pressure of 240 atmospheres at 385 C. over a catalyst consisting of active alumina with 15% of M003. The catalyst loading amounts to 2 kilograms of oil per litre of catalyst per hour. The refined product obtained has a base number of 35 milligrams of NH3 per litre of oil and is heated to 425 C. together with hydrogen without previous condensation at the same pressure and led over the synthetic aluminum silicate catalyst described in Example l. A gasoline is obtained with an octane number of according to the research method.

lf the same sump phase middle oil is refined so that the refined product has a base number of 2 milligrams, there is obtained by the subsequent destructive hydrogenation a gasoline with an octane number of 70 according to the research method.

What I claim is:

l. A process for the production of a high octane gasoline from a nitrogenous middle oil having a base number of more than 900, which comprises subjecting said nitrogenous middle oil to an incomplete refining by catalytic refining with hydrogen at temperatures of 350 to 460 C. and pressures of 10 to 300 atmospheres wherein the conditions of temperature, pressure and throughput are so correlated that the incompletely rened product has a base number of between 20 and 500, and then subjecting said incompletely refined product to a destructive hydrogenation at 330 to 550 C. under a pressure of to 700 atmospheres in the presence of at least one compound of a heavy metal of the 5th to 8th groups of the periodic system `which is applied to at least one silicate as a carrier. k

2. A process as claimed in claim l wherein the incomplete rening is carried out at a temperature Within the range of 380 to 450 C. with a throughput within the limits of 0.5 and 3 volumes per volume per hour in the presence of at least one compound of a metal of the 5th to 8th groups.

3. A process for the production of a high octane gasoline from a nitrogenous middle oil having a base number of more than 900 which comprises subjecting said nitrogenous middle oil to an incomplete refining by catalytic refining with hydrogen at temperatures of 350 to 460 C. and pressures of 10 to 300 atmospheres in the presence of atungsten-base catalyst wherein the conditions of temperature, pressure and throughput are so correlated that the incompletely refined product has a base number of between 20 and 500, and then subjecting said incompletely refined product to a destructive hydrogenation at 330 to 550 C. under a pressure of 150 to 700 atmospheres in the presence of at least one compound of a heavy metal of the 5th to 8th groups of the periodic system which is applied to at least one silicate as a carrier.

4. A process for the production of a high octane gasoline from a nitrogenous middle oil having a base number of more than 900 which comprises subjecting said nitrogenous middle oil to an incomplete refining by catalytic refining with hydrogen at temperatures of 350 to 460 C. and pressures of l0 to 300 atmospheres in the presence of a molybdenum-base catalyst wherein the conditions of temperature, pressure and throughput are so correlated that the incompletely rened product has a base number of between 20 and 500, and then subjecting said incompletely refined product to a destructive hydrogenation at 330 to 550 C. under a pressure of 150 to 700 atmospheres in the presence of at least one compound of a heavy metal of the 5th to 8th groups of the periodic system which is applied to at least one silicate as a carrier.

5. A process for the production of a high octane gasoline from a nitrogenous middle oil having a base number of more than 900 which comprises subjecting said nitrogenous middle oil to an incomplete refining by catalytic refining with hydrogen at temperatures of 350 to 460 C. and pressures of l() to 300 atmospheres in the presence of a nickel-base catalyst wherein the conditions of temperature, pressure and throughput are so correlated that the incompletely refined product has a base number of between 20 and 500, and then subjecting said incompletely refined product to a destructive hydrogenaton at 330 to 550 C. under a pressure of 150 to 700 atmospheres in the presence of at least one compound of a heavy metal of the 5th to 8th groups of the periodic system which is applied to at least one silicate as a carrier.

6. A process for the production of a high octane gasoline from a nitrogenous middle oil having a base number of more than 900 which comprises :subjecting said nitrogenous middle oil to an incomplete refining by catalytic refining with hydrogen at temperatures of 350 to 460 C. and pressures of l0 to 300 atmospheres in the presence of a coba1t-base catalyst wherein the conditions of temperature, pressure and throughput are so correlated that the incompletely refined product has a. base number of between 20 and 500, and then subjecting said incompletely refined product to a destructive hydrogenation at 330 to 550 C. under a pressure of 150 to 700 atmospheres in the presence of at least one compound of a heavy metal of the 5th to 8th groups of the periodic system which is applied to at least one silicate as a carrier.

References Cited in the tile of this patent UNITED STATES PATENTS 

1. A PROCESS FOR THE PRODUCTION OF A HIGH OCTANE GASOLINE FROM A NITROGENOUS MIDDLE OIL HAVING A BASE NUMBER OF MORE THAN 900, WHICH COMPRISES SUBJECTING SAID NITROGENOUS MIDDLE OIL TO AN INCOMPLETE REFINING BY CATALYTIC REFINING WITH HYDROGEN AT TEMPERATURE OF 350* TO 460*C. AND PRESSURES OF 10 TO 300 ATMOSPHERES WHEREIN THE CONDITIONS OF TEMPERATURE, PRESSURE AND THROUGHPUT ARE SO CORRELATED THAT THE INCOMPLETELY REFINED PRODUCT HAS A BASE NUMBER OF BETWEEN 20 AND 500, AND THEN SUBJECTING SAID INCOMPLETELY REFINED PRODUCT TO A DESTRUCTIVE HYDROGENATION AT 330* TO 550*C. UNDER A PRESSURE OF 150 TO 700 ATMOSPHERES IN THE PRESENCE OF AT LEAST ONE COMPOUND OF A HEAVY METAL OF THE 5TH TO 8TH GROUPS OF THE PERIODIC SYSTEM WHICH IS APPLIED TO AT LEAST ONE SILICATE AS A CARRIER. 